Multiplexing device for panoramic sonar systems

Claim 1

A multiplexing system for a panoramic sonar used in the formation of listening channels, said system comprising a transducer array comprising n rows of hydrophones equally spaced around the longitudinal axis of said antenna; a multiplexing means, having n inputs and one output, connected to said hydrophones, each hydrophone being connected to one input of said multiplexing means, said multiplexing means including address storage means associated therewith for selecting individual ones of said inputs, in succession, to appear at said output; a demultiplexing means with one input and n outputs, said one input of said demultiplexing means being connected to said output of said multiplexing means and said demultiplexing means including address storage means associated therewith for directing said input of said demultiplexing means to each of said n outputs, one at a time, in succession, said address storage means of said multiplexing means and said demultiplexing means being connected to a first source of pulse trains each containing synchronizing pulses for synchronizing the operation of both said address storage means; a second pulse source of r pulses, connected to said multiplexing means so as to cause said multiplexing means to step the operation of said address storage means of said multiplexing means out of sychronism with said demultiplexing means; and a time delay network, having one output and n inputs, for producing time delays corresponding to the relative distance a plane wave of sound echoes, traversing said transducer array, would travel between said hydrophones, said n inputs of said time delay network each being connected to at least one output of said demultiplexing means and said output of said time delay network forming the output of said system.